Evidence for improved sensitivity of within - participants analyses in tests of the theory of reasoned action

Two studies involving 26 behaviors were perforned to test four hypotheses. Between-participants and within-participants analyses of attitudes, subjective norms, behavioral intentions and actual behaviors suggested the following conclusions. First, consistent with Trafimow and Finlay (1996), the prediction of intentions from attitudes and subjective norms is better when within-participants analyses than between-participants analyses are used. Second, behavioral intentions are a good predictor of actual behavior, regardless of whether between-participants or within-participants analyses are used. Third, attitudes can predict unique variance in behaviors even when controlling for intentions, but it takes within-participants analyses to detect the effect. Fourth, subjective norms can predict unique variance in behaviors even when controlling for intentions, but it takes withinparticipants analyses to detect the effect. We conclude that within-participants analyses should be used for more sensitive tests of the theory of reasoned action. © 2001 Elsevier Science Inc. All rights